Algae outbreak threatens drinking water source

A villager steers his boat on the Chaohu Lake, which is covered by green algae in Anhui province on July 23, 2010. Despite cleanup efforts by the local government, the algae is spreading rapidly in China's fifth-largest freshwater lake, threatening the drinking water source for 300,000 residents in the city of Chaohu. [Photo/Asianewsphoto]